1. Field of the Invention
The invention relates generally to surgical devices and methods, and more particularly to shafts.
2. Description of Prior Art and Related Information
In various types of surgical procedures, particularly in endoscopy, a need exists for articulating, or bendable shafts. Such shafts are preferable, and often times necessary, for circumnavigating particular areas in the human body in order to reach a specific destination therein. Articulating shafts in the prior art include complex mechanisms that are expensive to manufacture and difficult to assemble. These complexities have derived, at least in part, from the need to provide tension in order to cause the shaft to bend.
Such shafts in the prior art include flexible portions which can bend in only one direction through the use of various types of tensioning mechanisms. Since the pathway to a particular desired location in a human body is often circuitous in more intricate surgical procedures, bending a shaft in only one direction can be very limiting. To overcome this deficiency, mechanisms to rotate a one-way bending shaft have been employed. Of course, having to manipulate a knob to rotate a shaft and then having to pull a tension mechanism to bend a shaft increases the complexity of a surgical procedure.
Prior art articulating shafts also include those that bend in opposite directions. Nonetheless, the bending of such shafts is accomplished by tension which means that at least two tensioning mechanisms are provided: one to cause the bend in a first direction, and the other to cause the bend in an opposite direction. Use of these types of shafts requires the technician to select the appropriate tensioning mechanism.
Articulating shafts in the prior art are also highly complex. These complexities have derived from the requirement of bending a distal portion of a shaft with a mechanism located at a proximal end of a medical device. Such complexities relate to both the manufacturing and operation of these devices. Prior art articulating shafts also lack rigidity. This is due at least in part to the fact that tensioning mechanisms in the prior art do not provide sufficient rigidity. Under standard use, prior art shafts are often unable to maintain a sufficient articulated form or shape.
No simple structure has been devised to accomplish ease of operation and flexibility with a desired rigidity.